The finished recipe. Cauliflower Cheese with Cannellini BeansIngredients 1 to 6. One head, about 500 g Cauliflower. Most of a tin, drained (200 g) Cannellini beans, tinned and drained (Drained weight.). 100 g Leek. 250 g Semi-skimmed milk. 15 g Cornflour (Thickens the sauce with no butter and keeps it gluten-free.). 50 g Reduced-fat cheddarIngredients 7 to 9. 1 tsp (6 g) Dijon mustard. Half a tsp Mustard powder. Plenty Black pepperStep 1. Boil the cauliflower florets and sliced leek in salted water for five minutes until just tender, drain well and tip into a baking dish with the beans.Step 2. Whisk the cornflour into a splash of the cold milk, then heat with the rest of the milk, stirring, until it thickens. Off the heat stir in most of the cheese, both mustards, salt and pepper.Step 3. Pour the sauce over, top with the last of the cheese and bake at 200°C for 20 minutes until bubbling and browned.